The production of water with hydrocarbons from subterranean wells constitutes a significant problem, because the processes that remove the water are costly and time consuming. While hydrocarbon-producing wells are usually completed in hydrocarbon-bearing formations, such formations may contain, or be near to, water-bearing sections. The high mobility of water may allow the water to flow into the well bore by way of natural fractures or high permeability sections present in the formation. Over the life of such wells, the ratio of water to hydrocarbons recovered may become undesirable in view of the cost of producing the water, separating the water from the hydrocarbons, and safely disposing of the water.
Many of the subterranean stimulation treatments used to enhance hydrocarbon production can increase the amount of water production. One such stimulation treatment is hydraulic fracturing. During hydraulic fracturing, a well bore is divided into intervals and each interval is separately fractured by pumping specialized fluids, such as aqueous fluids, into the subterranean formation at sufficient pressures to create or enhance at least one fracture and fracture face within the subterranean formation surrounding the well bore. These fractures increase fluid flow through the subterranean formation to the well bore. Of course, if the subterranean formation contains water, then the flow of water into the well bore will also be increased.
To make matters worse, the aqueous fluids typically used for hydraulic fracturing can also pass water into the well bore. For example, when water or an aqueous solution is pumped into an interval at a pressure sufficient to induce fractures, the fractures can inadvertently connect one interval of a well bore to another interval of the same well bore that has already undergone fracturing. This interconnecting fracture can allow water from the fracturing process of one interval to pass into another interval or another well bore that has already been fractured, completed, or even begun producing. Similarly, when well bores are located close to each other, then the water or aqueous solution pumped into an interval of one well bore during fracturing can pass from the interval of one well bore to the interval of another well bore that has already undergone fracturing. This interconnecting fracture can allow water from the fracturing process of one well bore to pass into another well bore that has already been fractured, completed, or even begun producing.
There is a need to prevent or minimize the amount of water that passes from one interval to another when intervals of a well bore undergo hydraulic fracturing in close proximity to each other.
There is a need to prevent or minimize the amount of water that passes from one interval to another when two or more wells undergo hydraulic fracturing in close proximity to each other.